The present invention relates to an active, divided stabilizer for a motor vehicle having an installed electric pivot motor for roll regulation.
Dividing a motor vehicle stabilizer into a first stabilizer part assigned to the suspension of the left wheel of a vehicle axle and a second stabilizer part assigned to the suspension of the right wheel of the vehicle axle is already known. If these stabilizer parts are pivotable in relation to one another around their shared longitudinal axis, significantly improved roll stability may be achieved in relation to suspensions having one-piece stabilizers, if a suitable pivot motor is provided between the two stabilizer parts, which pivots these stabilizer parts as needed in relation to one another on the basis of a suitable activation.
An electromechanical pivot motor has at least one electric motor and a mechanical transmission. A stabilizer is thus obtained whose two stabilizer parts, which are connected to one another by the electromechanical pivot motor, may be pivoted in a targeted way in relation to one another thereby, so that a desired stabilizer torque is generated, which prevents the rolling of the vehicle structure. Such a stabilizer is described in German Patent Document DE 198 46 275 A1.
In stabilizers having an installed pivot motor, the effective length which may be torqued is restricted in relation to typical stabilizers without a pivot motor. The active torsion length is composed of the length of the two stabilizer parts in the vehicle transverse direction. Due to this shortening of the active torsion length, because of the installed pivot motor, the fatigue strength values of the stabilizer may worsen. In addition, the characteristic of the motor vehicle upon suppression of roll movements is thus changed, because the overall spring rigidity increases.
The object of the present invention is to avoid these disadvantages as much as possible.
According to the present invention, a divided vehicle stabilizer having an installed pivot motor for roll regulation, which has at least one actuating drive made of electric motor and pivot motor transmission and a housing, at least one housing part being connected to an associated stabilizer part for torque transmission, is characterized in that the housing part has an axially oriented, central recess, into which the stabilizer part extends essentially up to its end and the connection for torque transmission between the housing part and the stabilizer part belonging thereto is located there.
This has the advantage that the stabilizer part is deflected by a larger distance at equal load and the suppression of the roll movement may thus be made softer and may be tuned more finely. The service life of the stabilizer may be increased. Due to the possibility of being able to use stabilizers having a smaller diameter, the vehicle weight is reduced and the production costs for the stabilizer are lower. The reduction of the passive stabilizer length due to the installation of the pivot motor is thus minimized, because of which lower spring rates may be achieved. This results in better comfort properties of a motor vehicle having an active stabilizer. The system behavior of the active roll stabilization system thus approaches that of a passive stabilizer. The basic design of suspensions for vehicles with and without active roll stabilization may thus be executed identically, which results in a significant cost reduction by using identical parts.
In an advantageous embodiment of the present invention, the electric motor is designed in such a way that its stator and rotor extend at least partially around the central recess of the housing part. The rotor of the electric motor may advantageously be mounted on the central recess of the housing part and may preferably be implemented as pot-shaped.
In a further advantageous embodiment of the present invention, the pivot motor transmission is a single-stage or dual-stage planetary gear or a harmonic drive transmission. The drive of the planetary gear advantageously occurs via a sun wheel and its output occurs via a planet carrier.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.